Question

7.3 kJ of energy required to melt 0.65 mol of ethylene glycol at its melting point. Calculate the 

molar enthalpy of fusion of ethylene glycol and the energy absorbed.

Answer 1

Standard enthalpy change of fusion of ethylene glycol $(Δ_{fus}H_o)= 9.9\ kJ/mol$

To melt 0.65 mol,

Q = ∆H × n = 9.9 × 0.65 = 6.435 kJ

$\therefore 6.435\ kJ$ is absorbed to melt the 0.65 mol of ethylene glycol.